A Greater Plurality of Calendars

[OwenM]

In what ways could we have more calendars in both official and predominant (in a given area) day to day use in modern times than OTL, and what could they be?
Obvious survivals boil down to "later adopters of the Gregorian calendar not doing so", but possible new departures include the World Calendar managing to capitalise on its high point of support in the 50s to be adopted in at least one country, the French or Soviet calendars (or perhaps more likely, different calendars introduced in similar circumstances) being more successful (come to think of it, in the French case, this could be helped by slower adoption of the Gregorian so it replaces a duplicity similar to metric OTL), or perhaps Dee's revised version of the Gregorian being forced on the C of E by the state in the late 1500s.
Any other suggestions are of course welcome.

 

[Elektronaut]

Maybe astrology never takes off in the ancient world. That's basically what prompted the push for more precise calendars and dating in antiquity.

 

[RyanF]

Ah, the World Calendar.

Fun spin on the Cold War if the Eastern Bloc were using the Soviet calendar and the West were using the World Calendar.

 

[Thande]

Maybe astrology never takes off in the ancient world. That's basically what prompted the push for more precise calendars and dating in antiquity.

Hard for us to appreciate now with light pollution, but it's kind of hard to imagine nobody ever looking up at night and thinking 'that looks interesting', especially when it could be used for utilitarian purposes like predicting when the Nile floods.

 

[OwenM]

Hard for us to appreciate now with light pollution, but it's kind of hard to imagine nobody ever looking up at night and thinking 'that looks interesting', especially when it could be used for utilitarian purposes like predicting when the Nile floods.

Although the Egyptians didn't have any leap days (which, given they used Sirius as a harbinger of said flooding and wrote that down frequently, seems to actually be a highly useful thing for dating when kings reigned in relation to now and not just each other).

 

[Dan1988]

Well, if mathematics became more of a thing among the Jewish people, then their calendar could be more optimized (along lines similar to this proposal from a U of T professor):
https://individual.utoronto.ca/kalendis/hebrew/rect.htm